TW200304167A - Exposure method and exposure device - Google Patents

Abstract

An exposure device is provided. In an exposure device EX, a mask M and a sensitive plate P move synchronously and a pattern of the mask M is projected onto the sensitive plate P through projection optical systems PL1 - PL5. The exposure device EX comprises the projection optical systems PL1 - PL5, a correction mechanism, a driving device and a control device CONT. The correction mechanism is disposed in the projection optical systems PL1 - PL5 for correcting an image property of the pattern projected on the sensitive plate P. The driving device is used to drive the correction device. The control device CONT sets one of a driving speed and a driving amount to the driving device according to a synchronous moving speed. Therefore, when correcting an image property and scanning and exposing, the pattern can be accurately overlapped at a pre-determined position by performing an accurate correction. As a result, the exposure device performs an accurate exposure process.

Description

200304167

V. Description of the invention (1) The technical field to which the invention belongs The present invention relates to an exposure method and an exposure device, and the exposure of the mask to the substrate while moving the mask and the substrate synchronously A scanning type exposure method and an electronic component that mounts a prior art liquid crystal display element or a semiconductor element are made by transferring a pattern formed on the photosensitive substrate to a so-called photolithography. The optical device used in this lithography etching process includes a photomask stage and a substrate table, and the photomask ^ stage is a two-dimensional movement of a photomask having a pattern. The stage is mounted on a photosensitive substrate and moved in a two-dimensional manner, so that the pattern formed on the mask is sequentially exposed and exposed on the photosensitive substrate by moving the mask machine and the board machine through a projection optical system. For the exposure apparatus, there are mainly two types of collective exposure apparatus and scanning exposure apparatus. Among them, the collective exposure apparatus enables the entire pattern of the photomask to be transferred onto the photosensitive substrate at the same time, and the scanning exposure apparatus uses one side of the photomask. The machine and the substrate machine synchronously scan one side so that the pattern of the photomask is continuously transferred on the photosensitive substrate. Among them, when manufacturing a liquid crystal display element, the requirement for the enlargement of the display field is mainly a scan type shading device. The electronic device includes a lithographic etching process in which a plurality of patterns are superimposed and formed in a predetermined positional relationship on a substrate by each process, and the substrate is deformed by the process. For example, when the substrate is a glass substrate for a liquid crystal display device, it is changed by the heat of each process.

l〇803pif.ptd Page 6 200304167 V. Description of the invention (2)-or when the metal layer is formed on the glass substrate, the glass substrate is deformed as if it is pulled by the metal layer in the direction of the surface. Occasion. When the substrate is deformed by the process, when the patterns are overlapped on the substrate, the patterns may deviate from each other. Therefore, don't set up a correction mechanism in the projection optical system of the exposure set to correct the $ characteristics projected on the substrate. Use this correction mechanism to perform the position or shape of the pattern image on the substrate according to the non-linear deformation of the substrate. The correction process is performed on the exposure side. That is, the exposure device is based on the non-linear deformation of the substrate to correct the displacement (shi ft) (positional error in the X-axis and Y-axis directions), SCaling (the expansion or reduction error of the image), rotation (rotation) (rotation error around the Z-axis), orthogonality (the amount of tilt in the Y-axis direction based on the X-axis of the image), etc., while exposing the pattern image on the substrate. The "correction mechanism" may be, for example, a parallel plane glass separation plate provided in the projection optical system. The parallel plane glass plate is driven by a motor or the like to force and dagger to correct the image characteristics. However, on the one side, the photomask and ί are moved, and the pattern is projected on a light-based exposure device via a projection optical system. According to the nonlinear deformation of the substrate, scanning exposure is performed on the positive mechanism side. At this time, the previous 闰 is driven (turned) at a certain speed by the drive mechanism of the motor. The image characteristics (such as the non-linear deformation of the Wj 3 plate, which corrects the pattern on the side); when scanning exposure is performed on the surface, the second surface is on the substrate. “The graph. In Figure UA, the arrow X1 indicates the scanning of the substrate " '', and the pattern image scans the substrate while allowing the drive mechanism to

200304167 V. Description of the invention (3) ------ Drive at a certain speed (turn) buckle ^ ^ 4 Μ β τ & and shirt on the substrate. As described above, the correction mechanism ί j and 板 of the broadcasting system is constant, and in FIG. 13A, the tilt Vd i is not the speed of the push P′1 (synchronous moving speed) Va is set to one position. By default, f is set on the substrate at equal intervals in the drawing direction. The interval Ta in the figure indicates that the reference point (for example, P4, P5, P5) i) passes from the positions PUP2, P3, and P4) to the position /-P ^ t elapsed time. That is, when the time Ta is short, the table = the scanning speed is fast, and when the time Ta is long, the scanning speed is higher. The dotted line indicates the target non-linear correction amount, and the solid line indicates real 1 = non-linear correction amount (actual pattern). However, the starting point of the driving mechanism of the correction mechanism is the time point when the substrate moves in the scanning direction, that is, the time point at which each of the positions p 1 to P 5 passes the reference point. In the example shown in Fig. 13a, the relationship between the scanning speed Va of the substrate and the driving speed (correction speed) Vd of the correction mechanism according to the deformation of the substrate is appropriate, and the target non-linear correction 9 amount is consistent with the actual non-linear correction. However, the correction mechanism of the previous exposure device was problematic. η ^ _ exposure ^ light ^ is equipped with a light source for illuminating the exposure light, the light source is Ik, which deteriorates with the passage of time so that the amount of light (illumination) decreases. Because the earth surface causes the photomask and the substrate to move synchronously, the scanning exposure device that exposes the pattern of the optical system through the projection lens of the projection lens f fΐ to the scanning type exposure device. Ϊ 2 changes the synchronous moving speed according to the decrease in the amount of light from the light source. The volume of the body is slowed down according to the low amount of light from the light source, and the exposure amount on the substrate can be controlled to be at the desired level "; the speed of movement

10803pif.ptd Page 8 200304167 V. Explanation of the invention (4) However, the previous correction mechanism is driven by a certain driving speed V d, as shown in the pattern diagram in Figure 1 3 B, in order to obtain the desired exposure When the scanning speed of the photosensitive substrate becomes slower than Va and becomes Vb (at this time, 'time Tb is longer than time Ta'), the driving start point of the correction mechanism is set at the time when each position P1 ~ P5 passes the reference point As for the relationship between the reference point passing from the position P 1 on the substrate to the position P 2 passing, the driving of the correction mechanism is stopped (the driving speed Vd becomes 0), and the target non-linear correction amount and the actual non-linear correction amount are inconsistent. In particular, In this case, as shown in Fig. 13B, the correction amount is intermittent and cannot be performed smoothly. On the one hand, for example, when the scanning speed becomes faster when the output of the light source is changed by different methods, in this case, as shown in Figure 1C, the scanning speed of the photosensitive substrate is made faster than Va and becomes Vc. (At this time, time Tc is shorter than time T a), the driving start point of the correction mechanism is set at the time when the positions P 1 to P 5 pass the reference point, and the simultaneous driving speed V d is a certain relationship. The driving of the correction mechanism between the passage of position P1 to the passage of position P2 on the substrate is not completed. The actual non-linear correction amount is inconsistent with the target non-linear correction amount. In this way, when the target correction amount deviates from the actual correction amount, a problem arises in that the pattern formed on the substrate cannot make the next pattern overlap with a predetermined position relationship with good accuracy. Previously, although the deviation between the target non-linear correction amount and the actual non-linear correction amount was within the allowable range, in recent years, the deviation of the actual non-linear correction amount of the target non-linear correction amount has been demanded by the miniaturization of the pattern. degree. Summary of the invention

10803pif.ptd Page 9 200304167 V. Description of the invention (5) The purpose of the present invention is to provide an exposure method and exposure equipment in view of such problems, and correct it on one side after scanning. At the time of clamping, fine precision correction can be performed, and the pattern can be refocused to a predetermined position relationship at a good 2 degrees while performing accurate exposure processing: The present invention that solves the above-mentioned problem adopts corresponding to the implementation diagram ~ the first 2 The following structure of the figure. y. The exposure method of Benming is to make the mask (M) and the substrate (p) move synchronously through the projection light system (PL1 ~ PL5) to project the pattern of the mask (M) on the substrate (P). The exposure method is characterized by correcting the position of the pattern image projected on the substrate (P) by a correction mechanism (23, 28, 31, 27) provided in the projection / optical system (PL1 to PL5), and simultaneously The correction speed (Vx34a, Vy34a, VR34a, VSk) or correction amount (x34a, y34a, r 34a, Sk) of the position of the correction image is set in accordance with the synchronous movement speed. According to the present invention, the relationship between the correction speed or the correction amount for correcting the position of the pattern image projected on the substrate is set according to the synchronous movement speed of the photomask and the substrate. Although the synchronous movement speed changes, the target correction amount and the actual correction amount can be set. Consistent. Therefore, the pattern can be superimposed on a predetermined positional relationship with good accuracy, and the exposure processing can be performed with high accuracy. The exposure device (EX) of the present invention is for exposing the mask (M) and the substrate (p) on one side so as to move synchronously through the projection optical system (PL) to project the pattern of the mask (M) on the substrate (P) for exposure. The device is characterized by including a correction mechanism (23, 28, 31, 27) " drive device (50A, 50B, 51A, 51B, 52) and a control device (CONT). Among them, the correction mechanism (23, 28, 31, 2 7) is provided in the projection optical system (p L 1 to P L 5), and the projection is corrected to the base

10803pif. Ptd Page 10 200304167 V. Description of the invention (6) Image characteristics of the pattern of the plate (P). The driving device (50A'50B, 51A, 51B, 52) is a driving correction mechanism (23, 28, 31, 27). The control device (CONT) sets at least one of a driving speed and a driving amount in the driving device (50A, 50b, 5 1 A, 5 1 B, 5 2) in accordance with the synchronous moving speed. According to the present invention, a correction mechanism for correcting the image characteristics of a pattern projected on a substrate is provided in the projection optical system, and the relationship between the driving speed or the driving amount of the driving device for driving the correction mechanism is set according to the synchronous movement speed of the mask and the substrate. When the synchronous movement speed is changed, the target correction amount can be consistent with the actual correction amount. Therefore, it is possible to superimpose the patterns at a predetermined positional relationship with good precision 'and perform the exposure processing with good precision. The exposure device (EX) of the present invention is an exposure system in which the mask (M) and the substrate (p) are moved on one side in synchronization with the projection optical system (PL) to project the pattern of the mask (μ) on the substrate (P). The device is characterized by including a correction mechanism (23, 28, 31, 27), a driving device (50A, 50B, 51A, 51B, 52), and a control device (CONT). Among them, the correction mechanism (23, 28, 31, 27) is provided in the projection optical system (pli ~ PL5), and corrects the image characteristics of the pattern projected on the substrate (P). The driving devices (50 A, 50 B, 5 1 A, 5 1 B, 5 2) are drive correction mechanisms (2 3, 2 8, 3, 1, 7). The control device (CONT) sets at least one of the driving speed and the driving amount in the driving device (50A, 50B, 51A, 51B, 52) according to the position of the mask (M) or the substrate (P). According to the present invention, a correction mechanism for correcting the image characteristics of a pattern projected on a substrate is provided in the projection optical system, and is set according to the position of the mask or the substrate.

10803pif.ptd Page 11 200304167 V. Explanation of the invention (7) The relationship between the driving speed or the driving amount of the driving device of the driving correction mechanism, although the target deformation amount can be consistent with the actual correction amount when the substrate is deformed, non-linear correction can be performed well. . Therefore, the patterns can be superimposed at a predetermined position relationship with good accuracy, and the exposure processing can be performed with good accuracy. According to the exposure method and the exposure device of the present invention, the relationship between the correction speed or the correction amount for correcting the image position of the pattern projected on the substrate is set in accordance with the synchronous movement speed of the mask and the substrate. Make the target correction amount consistent with the actual correction amount. Therefore, the patterns can be superimposed at a predetermined positional relationship with good accuracy, and exposure processing can be performed with good accuracy. In order to make the above principles and other objectives, features, and advantages of the present invention more comprehensible, a preferred embodiment is described below in detail, in conjunction with the accompanying drawings, as follows: Embodiments The following is an exposure of the present invention. The method and the exposure device will be described with reference to the drawings. Fig. 1 is a schematic configuration diagram showing an embodiment of an exposure apparatus of the present invention, and Fig. 2 is a schematic perspective view of Fig. 1. In FIGS. 1 and 2, the exposure system EX includes an illumination optical system IL, a mask table MST, a plurality of projection optical systems PU to P5, a substrate table PT, and a mask-side laser interferometer 39a, 39b And substrate-side laser interferometers 39a and 39b. The illumination optical system IL includes a plurality of illumination system modules 10a to 10e that illuminate the mask M with exposure light. Photomask table MST is a photomask μ. The digital projection optical system PL and PL5 are arranged to correspond to each of the lighting system components 1 0 a to 1 0 e, so that a mask illuminated by exposure light is used.

10803pif. Ptd Page 12 200304167 V. Description of the invention (8) The image of the pattern of M is projected on the photosensitive substrate (substrate) p. The substrate table PST supports a photosensitive substrate P. The mask side laser interferometers 3 9 a and 3 9 b use laser light to detect the position of the mask machine MST. The substrate-side laser interferometers 43a and 43b detect the position of the substrate table PST using laser light. In this embodiment, the lighting system components are five of 10a to 10e. In FIG. 1, for convenience, only those corresponding to the lighting system component 1a are shown, and each lighting system component 10a to 1 0 e system has the same structure. The photosensitive substrate p is a glass substrate coated with a photoresist (photosensitizer). In the exposure apparatus EX of this embodiment, the pattern of the mask μ is patterned through the projection optical system PL while the mask M supported by the mask table MST and the photosensitive substrate p supported by the substrate table pST are moved synchronously. A scanning type exposure apparatus that projects and exposes a photosensitive substrate P. In the following description, the direction of the optical axis of the projection optical system PL is the z-axis direction, which is perpendicular to the z-axis direction, and the synchronous movement direction (scanning direction) of the mask M and the photosensitive substrate ρ is the x-axis direction. A direction orthogonal to the Z-axis direction and the X-axis direction (non-scanning direction) is the Y-axis direction. As shown in FIG. 1, the illumination optical system includes an exposure light source 6, an ellipsoid mirror 6a, a dichroic mirror 7, a wavelength selection filter 8, and a light guide. 9. The ellipsoid mirror 6a focuses the light beam emitted from the light source 6. The dichroic mirror 7 reflects light beams of a wavelength necessary for exposure from the light beams collected by the ellipsoid mirror 6a, and transmits light beams of other wavelengths. The wavelength-selective filter 8 passes the reflected light from the dichroic mirror 7 and passes only the wavelength necessary for exposure. The light guide unit 9 divides the light beams from the wavelength selection filter 8 into a plurality of lines (in this embodiment, five lines),

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Page 13 200304167 V. Description of the invention (9) The light-transmitting mirror 11 is incident on each lighting system component 10a to 10e. In this embodiment, the exposure light source 6 is a mercury lamp, and the exposure light is selected by a wavelength selection filter 8. The g-line (4 3 6 nm), h-line (40 5 nm), and hiM365 nm are used for the wavelength necessary for exposure. Wait.

The lighting system component 1 0 a includes an illumination shutter (shu 11 er) 1 2, a relay lens (re 1 ay 1 ens) 1 3, an optical integrator (optica 1 i nt egrator) 1 4, and a focusing lens (condenser 1 ens) 1 5 ° Wherein, the optical integrator 14 adjusts the light beam passing through the relay lens 13 so that the light beam having a substantially uniform illumination distribution is converted into exposure light. The focusing lens 1 5 condenses the exposure light from the optical integrator 14 to illuminate the mask M with uniform illumination. In this embodiment, the lighting system components 10 b to 10 e having the same structure as the lighting system component 10a are arranged at a certain interval in the X-axis direction and the γ-axis direction. The lighting shutter 12 is arranged on the downstream side of the light path of the light guide 9 to the light path of the light beam so that it can move forward and backward freely, and the light beam can be shielded and released. The lighting shutter 12 is provided with a shutter driving unit 12 D 'that moves the lighting shutter 12 forward and backward in the optical path, and its driving is controlled by a control unit 〇 Ν Τ.

The lighting system component 10a (10b ~ 10e) has a light amount adjustment mechanism. The light amount adjustment mechanism 18 is to adjust the exposure of each meter by setting the illuminance of the light beam in each optical path, including a semi-transparent mirror (h? Lfiirror 19), a detector (detector 2), A filter 21 and a filter driving section 21D. The semi-transparent mirror 19 is disposed in the optical path between the filter 21 and the relay lens 13 so that a part of the light beam that has passed through the filter 21 enters the detector 20. Each detector 20 is often

200304167 V. Description of the Invention (ίο) The illuminance of the incident beam is independently detected, and the detected illuminance signal is output to the control device CONT. The filter 21 is patterned in a stripe pattern using chromium (Cr) or the like on a glass plate, and is formed so that the transmittance gradually changes into a linear shape in a certain range along the Y-axis direction, and the lighting shutters arranged in each optical path 1 2 And translucent mirrors 19. These semi-transparent mirrors 19, detectors 20, and filters 21 are each arranged in a plurality of optical paths. The filter driving section 2 1D moves the filter 21 in the Y-axis direction according to an instruction from the control device CONT. The filter 21 is driven by the filter driving section 2 1 D to adjust the light amount of each optical path. The light beam transmitted through the light amount adjusting mechanism 18 reaches the optical integrator 14 through the relay lens 13. A secondary light source is formed on the exit surface side of the optical integrator 14 and the exposure light from the optical integrator 14 is irradiated with a uniform light intensity through the mask M supported by the mask machine MST through the focusing lens 15. However, the exposure light emitted from each of the lighting system components 10 a to 10 e is irradiated in different illumination areas on the mask M. The mask machine MST supporting the mask M is set to be possible-movable, and has a long stroke in the X-axis direction for performing one-dimensional scanning exposure and a stroke in a predetermined distance in the Z-axis direction orthogonal to the scanning direction. As shown in Fig. 1, the mask table MST includes a mask table driving section MSTD for driving the mask table MST in the X-axis direction and the Z-axis direction. The mask table driving unit MSTD is controlled by the control unit CONT. As shown in FIG. 2, the mask-side laser interferometer includes an X laser interferometer 39a and a Υlaser interferometer 39b. Among them, the X laser interferometer is the detection mask. The position of the MST in the X axis direction, and the Y laser interferometer 3 9b is the detection mask.

10803pif.ptd Page 15 200304167 V. Description of the invention (11) The position of the machine M S T in the Y-axis direction. An X moving mirror 38a extending in the Y-axis direction is provided on the + χ side edge of the mask table M s τ. On the one hand, at the + Y side end edge of the mask machine M S T is provided a Y moving mirror 38b that extends orthogonally to the X moving mirror 3 8 a in the X-axis direction. In the X-moving mirror 38a, the X laser interferometer 39a is arranged in an opposite direction, and in the Y-moving mirror 38b, the γ laser interferometer 39b is arranged in an opposite direction. The X laser interferometer 39a makes the laser light irradiate the krypton moving mirror 38a. The light (reflected light) generated by the irradiation of the laser light on the X moving mirror 38a is received by the detector inside the X laser interferometer 39a. The x-laser interferometer 39a detects the position of the x-moving mirror 38a based on the reflected light from the 乂 moving mirror 38a, based on the position of the internal reference mirror, that is, the position of the mask machine MST in the x-axis direction. In addition, the position of the mask M is measured in advance on each position of the mask M of the mask machine MST, and can be monitored by a laser interferometer inspection value. The Y-axis laser interferometer 39b causes the laser light to irradiate the gamma moving mirror 38b. The light (reflected light) generated by the irradiation of the laser light on the Y moving mirror 38b is received by the internal laser γ detector of the gamma laser v dry instrument. The γ laser interferometer 39b is based on the reflection from the Y moving mirror 38b. The position of the γ moving mirror 38b is detected based on the position of the internal reference mirror, that is, the mask machine MST (therefore, the mask is in the ¥ direction. Position. The detection results of the radio interference interferometers 39a and 39b are output to the control dream, and 绖; 丨 mask machine driver MSTD drives the mask machine MST to control the position of the mask M. Early machine mouth MbT, the exposure light passing through the mask M is incident on each projection optical system

10803pif. Ptd page 16 200304167 V. Description of the invention (12) P L 1 ~ P L 5. Each of the projection optical systems p L 1 to P L 5 projects and exposes a pattern image existing in the illumination area of the mask μ onto the photosensitive substrate ρ, and is arranged so as to correspond to each of the lighting system components 10adOe. The projection optical systems PL1, PL3, jTL5 and the projection optical systems P L 2 and P L 4 are arranged in two rows in a zigzag pattern. That is, each of the projection optical systems p L 1 to PL 5 arranged in a zigzag shape, and adjacent projection systems (for example, the projection optical systems PL1 and PL2, PL2 and PL3) are arranged in the X-axis direction with a predetermined displacement amount. . The exposure light that has passed through each of the projection optical systems p L 1 to ρ [5 is a different projection area of a pattern image corresponding to the irradiation area of the mask M on a photosensitive substrate P supported by the substrate table PST. The pattern of the photomask M in the lighting field is transferred onto the photoresist-coated photosensitive substrate P with predetermined image characteristics. The substrate machine PST supporting the photosensitive substrate P is set to be movable, and has a long stroke in the X-axis direction for one-dimensional scanning exposure, and a length in the Z-axis direction that moves in steps in the direction of the direct parent to the scanning direction. stroke. The substrate table PST includes a substrate table driving unit p s T D that drives the substrate table PST in the X-axis direction and the Y-axis direction, and further drives the Z-axis direction. The substrate machine drive PSTD is controlled by the controller CONT. As shown in Fig. 2, the substrate-side laser interferometer system includes an X laser interferometer 43a and a Y laser interferometer 43b. Among them, the X laser interferometer 43a detects the position of the substrate table PST in the X axis direction, and the γ laser interferometer 43b detects the position of the substrate table PST in the Y axis direction. An X-moving mirror 42a extending in the γ-axis direction is provided on the edge of the + sense side of the substrate table pST. An end edge of the -Y side of the substrate table PST is provided with a Y moving mirror 42b extending orthogonally to the X moving mirror 42a and extending in the X axis direction. The X-moving mirror 4 2a is arranged to face the X-laser interference

10803pif.ptd Page 17 200304167 V. Description of the invention (13) --- Instrument 4 3a, the Y moving mirror 4 2b is oppositely arranged with a gamma laser interferometer 43b. The X laser interferometer 43a irradiates laser light to the X moving mirror 42a. The light (reflected light) generated by the irradiation of the laser light on the X moving mirror 42a is received by the detector inside the X laser interferometer 43a. The χ laser interferometer 43a detects the position of the X-moving mirror 42a based on the reflected light from the 乂 moving mirror 42a, using the position of the internal reference mirror as the reference, that is, the substrate table pST (and thus the photosensitive substrate P) at X-axis position. The Y laser interferometer 4 3b irradiates laser light to the γ moving mirror 42b. The light (reflected light) generated by the laser light irradiating the Y moving mirror 42b is received by the detector inside the gamma laser interferometer 43b. The γ laser interferometer 43b detects the position of the Y moving mirror 42b based on the reflected light from the Y moving mirror 4 2 b based on the position of the internal reference mirror, that is, the position of the substrate table pST in the γ axis direction. In addition, the position of the 'photosensitive substrate P' is measured in advance on each position of the photosensitive substrate P of the substrate machine PST, and can be monitored by the inspection value of the laser interferometer. The detection results of the laser interferometers 43a and 43b are output to the control device CONT °, and the position of the photosensitive substrate p held by the substrate machine PST in the z-axis direction is one of the focus detection systems of the oblique incidence method. Multi-point focus position detection system (not shown) detects it. The result of the multi-point focus position detection system is output to the control unit CONT. The control device CO NT is based on the detection results of the laser interferometers 4 3 a, 4 3 b, and the multi-point focus position detection system. The substrate device p ST is driven via the substrate device driving unit p S τ D to perform Position control of the photosensitive substrate P.

10803pif. Ptd Page 18 200304167 V. Description of the invention (14) Each mask machine MST and substrate machine PST is under the control of the control device CONT. The mask machine driving unit MSTD and the substrate machine driving unit PSTD can Move independently. However, in this embodiment, the mask table MST supporting the mask M and the substrate table PST supporting the photosensitive substrate P are moved synchronously to the projection optical system PL in the X-axis direction at an arbitrary scanning speed (synchronous moving speed). 0 Here, as shown in FIG. 2, the exposure apparatus EX includes a mask table speed detection device 71 and a substrate table speed detection device 72. Among them, the mask machine speed detection device 71 detects the movement speed of the mask machine MST in the X-axis direction (ie, the synchronous movement speed), and the substrate machine speed detection device 72 detects the substrate machine PST in the X-axis direction. Movement speed (ie, synchronous movement speed). The detection results of the mask table speed detection device 71 and the substrate table speed detection device 72 are output to the control device cONT. FIG. 3 is a schematic configuration diagram of a projection optical system pli (PL2 to PL5). Here, FIG. 3 shows only those corresponding to the projection optical system pL 1, and each of the projection optical systems PL1 to PL5 has the same configuration. Each of the projection optical systems P L 1 to P L 5 includes a displacement adjustment as shown in Fig. 3 2 5. A field-of-view light adjustment mechanism 23, two sets of reflection-refraction optical systems 24 turns 26, and a magnification adjustment mechanism (correction mechanism) 27. The light beam transmitted through the mask M is incident on the displacement adjustment mechanism 23. The displacement adjustment mechanism 2 3 is provided with a rotating parallel plane glass plate (positive mechanism) 2 3Α around the Z axis and a rotating parallel plane glass plate (compensating mechanism) 23B around the X axis. The parallel plane glass plate 23A is driven by a motor or the like 50A rotates around the y-axis, and the parallel plane glass plate 23B is driven by a motor or the like ^

200304167 V. Description of the invention (15) The moving device 50B rotates around the X axis. The pattern image of the mask M on the photosensitive substrate P is rotated around the Y axis by the parallel plane glass plate 23A, and the light on the photosensitive substrate ρ is rotated around the X axis by the parallel plane glass plate 2 3 Β. The pattern image of the cover M is displaced in the Z axis direction. The driving speed and driving amount of the driving devices 50a and 50B are independently controlled by the control device CONT. Each of the driving devices 50 A and 50 B rotates each of the parallel flat glass plates 23A and 23B at a predetermined speed (a predetermined angle) according to the control of the control device C 〇 ΝΤ. The light beam that has passed through the shifting spheroidizing mechanism 23 is incident on the first group of reflection-refraction optical systems 24. The reflection-refractive optical system 24 is an intermediate image 'forming a pattern of the mask µ, and includes a right-angled lens (correction mechanism) 28, a lens 29, and a concave mirror 30. The right angle 稜鏡 28 is provided so as to be rotatable around the z-axis, and a drive device 51A such as a motor is used to turn around the z-axis. The pattern image of the mask M on the photosensitive substrate P which is rotated around the two axes by the right-angle prism 28 is rotated around the z axis. Controlled by the control device cont. The driving device 5 1 A is rotated in accordance with the control device c 〇 T > 4 ^ soil 丨. (Predetermined angle). Work 1, so that the right angle 稜鏡 28 is arranged at a predetermined amount. Projection area of the middle image of the pattern formed by the video system 24. Aperture through the field of vision? The iris 2 6 sets the refractive optical system 25 on the photosensitive substrate ρ. The beam is incident on the second group of retroreflective optical system 25, which is the same as the retroreflective optical system 2 4

200304167

For example, including the structure with the function of turning adjustment) 31, the lens 32 and the concave mirror are based on the ancient JVo, the motor 51B is moved on the Z axis ^ °, / the wire angle 稜鏡 j1 is also driven by the motor, etc. Figure fools around, f turns around, hunting makes the photosensitive substrate 15-"image revolves around the z-axis. The driving device & the moving speed and driving amount are controlled by the control device wrnMT: ΜΜ 勒 51B drive basis control device CONT The second set C: N = two 'drive device 51 B system turns the fixed amount (predetermined angle ^ causes the right-angled mausoleum 31 to return to the beam-emission mechanism from the reflective refractive optical system 2 5 at a predetermined speed (/ 1 positive mechanism) 27. Make the image of the photomask M on the photosensitive substrate P upright and equal. The magnification adjustment mechanism 27 is composed of three lenses, for example, a convex lens and a plano-convex lens, and is convex; between the mirror and the plano-convex lens. The two convex lenses at the position are moved in the Z-axis direction to adjust the scaling of the pattern image of the mask M. At this time, the two convex lenses are moved by the driving device 52, and the driving device 52 is controlled by the control device cONT. The driving device 52 is based on the control of the control device CONT. The movement at a predetermined speed is quantified. The second figure 4 is a plan view showing the projection areas 34a to 34e of the projection optical systems PL1 to PL5 on the photosensitive substrate p. Each area of each projection area 34a to 34e is set by the field aperture μ. It has a predetermined shape and has a mesa shape in this embodiment. The projection collars 34a, 34c, 34e and the projection areas 34b, 34d are arranged in the X-axis direction in the _ direction. Furthermore, each adjacent projection of the projection areas 34a to 34e. The ends (borders) of the realms (35a and 35b, 35c and 35d, 35e and 35ί, 3 5g and 35h) are shown in two dotted lines in parallel, overlapping in the direction of the Z axis

10803pi f. Ptd page 21 200304167 V. Description of the invention (17) The configuration ′ is set to be approximately equal in total in the projection area of the X-axis direction. That is, 'is set so that the exposure amounts are equal when scanning exposure in the X-axis direction. In this way, a change in optical aberration or a change in illuminance at the joining portions 3 6 a to 3 6 d becomes smooth from the joining portions 3 6 a to 3 6 d overlapped by each of the projection areas 34a to 34e. Moreover, although the shape of the projection fields 3 4 a to 3 4 e in this embodiment is a mesa shape, it may be a hexagonal shape or a rhombic shape, or a parallelogram. Returning to FIG. 1, a detector 4 i is arranged on the substrate table PST approximately at the same height as the exposure surface of the photosensitive substrate P. The detector 41 is an illuminance sensor that detects information (illuminance) on the light quantity of the exposure light on the photosensitive substrate 1 ", and is composed of a CCD sensor, and detects the correspondence between each of the projection optical systems PL1 to PL5 on the photosensitive substrate p The illuminance of the exposure light at each position makes the detection signal wheel detected by the control device CO NT. The detector 41 is provided by a guide shaft (not shown) arranged on the substrate table PST in the γ-axis direction at the same level as the photosensitive substrate P, and is set by the detector driving section in the scanning direction ( X-axis direction) moves in the direction orthogonal to (γ-axis direction). The detector 41 is a projection corresponding to the projection optical system PL and PL5 by the movement of the substrate table PST in the X-axis direction and the movement of the γ-axis direction by the illuminance sensor driving section before one or more exposures. Areas 34a ~ 3e are scanned with jealousy. Therefore, the illuminance of the exposure light of the projection areas 34a to 34e on the photosensitive substrate P and the boundary portions 35a to 35h of each of the projection areas 34a to 34e is detected in a two-dimensional manner by the detector 41. The illuminance of the exposure light detected by the detector 41 is output to the control device CO NT. At this time, the control device C0NT is composed of the substrate machine driving section PSTD and the detector driving section.

10803pif.ptd Page 22 200304167

Each driving amount can be detected by the position of the detector 4 丨. Figures 5A and 5B show the projection area on the photoreceptor substrate M1, which is adjusted by the projection mechanism 23, and the projection area on the tuyou r (Figure 荦 is a schematic view of the situation. Μ is the position of M4a

As shown in FIG. 5A, the position of the displacement adjustment mechanism 23-2 A at the reference position shown by the solid line in the figure is thousands; Thousands: = J ^ ^ tz ^ ^^ 5β ® ^ ^ 2 2 projection area 43a ( 43ai) is set at the second position: the dashed line of the second figure ... the parallel plane glass plate "A is driven by the driving device 50A around the γ axis and rotates by a predetermined amount, as shown in the dotted line in Figure 5B, The position of the projection area 34a (34a) on the photosensitive substrate ρ is shifted by a certain amount in the X-axis direction. Here, the amount of movement from the projection area 34ai to the projection area 34 ~ on the photosensitive stomach substrate P (correction) The amount 'that is, the position of the projection area 34a on the photosensitive substrate P in the X-axis direction' is set according to the rotation amount (angle, that is, the driving amount of the driving device 50A) of the γ-axis peripheral circle of the parallel flat glass plate 2 3a In addition, the moving speed (correction speed) Vx34a from the projection area 34a! To the projection area 34a2 is set according to the rotation speed around the Y axis of the parallel flat glass plate 23 A ^, that is, the driving speed of the driving device 50A. Similarly, Projection of the projection area 34a on the photosensitive substrate P in the Y-axis direction The amount (correction amount) y34a is set according to the rotation amount of the parallel plane glass plate 23B in the X-axis periphery, that is, the driving amount of the driving device 5 0 B. The movement speed (correction speed) of the projection area 34a in the Y-axis direction ) Vy34a is the rotation speed of the flat glass plate 23 B around the X axis in accordance with + line, that is, the driving device f

10803pif.ptd Page 23 200304167 V. Description of the invention (19) The driving speed of 5 0 B is set. Moreover, the same applies to the rotation correction. As shown in FIG. 6A, the rotation amount R34a of the area 34a is projected on the photosensitive substrate P, that is, the position of the area 34a in the direction around the Z axis is projected on the photosensitive substrate P according to the triangle.稜鏡 28, 31 The amount of rotation around the Z axis, that is, the drive amount of the driving devices 51A, 51B is set, and the rotation speed (correction speed) of the projection area 34a VR34a is based on the triangle 稜鏡 2 8, 3 1 on the Z axis The surrounding turning speed, that is, the driving speed of the driving devices 51A, 51B is set. The same is true for the magnification correction. As shown in FIG. 6B, the magnification (correction amount) Sk of the projection area 34a on the photosensitive substrate P is the amount of movement in the Z-axis direction according to the magnification adjustment mechanism 27, that is, the driving of the driving device 52 The amount is set, and the rate of change (correction speed) VSk in the projection area is set in accordance with the movement speed of the magnification adjustment mechanism 27 in the Z-axis direction, that is, the driving speed of the driving device 52. However, by driving these displacement adjustment mechanisms, rotation adjustment mechanisms, and magnification adjustment mechanisms simultaneously or selectively, the position and shape of the projection area 3 4 a on the photosensitive substrate can be arbitrarily set. In the above description of the projection area 3 4 a, and for other projection areas 3 b to 3 4 e ', it is also possible to use each of the shift adjustment mechanisms, rotation adjustment mechanisms, and magnification adjustment mechanisms provided in each projection optical system pL2 to pL5. The position and shape on the photosensitive substrate p can be arbitrarily set by simultaneous or selective driving. As shown in FIG. 7 ', a pixel pattern (common pattern) 44 is formed in the pattern area of the mask 1 ^, and the two ends of the pixel pattern 44 in the γ-axis direction are formed.

10803pif.ptd Page 24 200304167 V. Description of the Invention (20) Peripheral circuit patterns (non-common patterns) placed 4 5a, 45b. The pixel pattern 44 is a pattern in which a plurality of electrodes are arranged in a regular pattern in accordance with a plurality of pixels. The peripheral circuit patterns 45a and 45b are driving circuits for forming electrodes for driving the pixels 44 and the like. Also, around the pattern area of the mask M, mask marks 4 5a to 4 6d are formed at the corners of the mask M. The mask marks 4 6 a to 4 6d are calculated using various correction amounts during positioning of the mask M, and are formed in a cross shape with chromium ((: 1 «), etc.) Furthermore, in the mask M, along the X-axis direction The mask positioning marks 5 6a and 5 6b are formed at the near positions of the center of both sides of the edges (that is, the centers of both ends in the y-axis direction of the mask M). The mask positioning marks are used to align with the position of the photosensitive substrate ρ. 'Like the mask marks 46a to 46d, it is formed in a cross shape by chromium. Like the mask M, as shown in FIG. 8, around the projection area of the photosensitive substrate P, at the corner of the photosensitive substrate P The substrate mark 4 7a ~ 4 7d is formed at the position. The substrate mark 4 7a ~ 4 7d is calculated by using various correction amounts for positioning of the photosensitive substrate. It is formed by a transparent portion formed in a cross shape by chromium and the like. The substrate positioning marks 5 7a and 5 7b are formed near the center of the edges of both sides in the X-axis direction (that is, the centers of both ends in the Y-axis direction of the photosensitive substrate P). The substrate positioning marks are used to align with the position of the photomask M, Similar to the above-mentioned substrate marks 47a to 47d, they are made of chrome or the like. Into the shape of a cross section of the transmission. Such identification reticle 46a~46d, and mask positioning substrate identification 47a~47d

10803pif.ptd Page 25 200304167 V. Description of the invention (21) The marks 56a, 56b and the substrate positioning marks 57a, 57b are provided by the positioning system (position detection section) located above the photomask M in Figure 2 4 9 a, 4 9 b to test. The positioning systems 49a and 49b have a driving mechanism (not shown) that moves in the X-axis direction, and are configured to retreat from the lighting field during scanning exposure. Next, a method of exposing the pattern of the photomask M to the photosensitive substrate P using the above-mentioned exposure device will be described. Here, as shown in Figure 4, the length of the long side is 1 ^ 1, the length of the short side is 1 ^ 2, and the interval between adjacent projection areas (in the projection The distance in the γ-axis direction of the field) is L 3. As shown in FIG. 8, the pixel pattern 50 and the peripheral circuit patterns 5ia and 5ib at both ends in the y-axis direction of the pixel pattern 50 are formed on the photosensitive substrate ρ, and the peripheral circuit patterns 51a and 51b of the photosensitive substrate P are formed. The peripheral circuit patterns 45a and 45b of the mask M shown in FIG. 7 are formed by projection exposure of the projection optical systems p L 1 and PL 5 on both outer sides of the plurality of projection optical systems. At this time, the peripheral circuit patterns 4 5 a and 4 5 b of the mask M are projected and exposed on the photosensitive substrate ρ through the projection optical systems PL1 and PL5 to form the peripheral circuit patterns 5 1 a and 5 1 b. Photomask μ. However, the peripheral circuit patterns 51a and 51b of the photosensitive substrate P and the peripheral circuit patterns 45a and 45b of the photomask M are formed in the same size and shape. In addition, the length of the pixel pattern 50 'in the photosensitive plate {) in the X-axis direction is L5, and the length in the Y-axis direction is L6. On the one hand, in the pixel pattern 44 of the mask μ, the length in the y-axis direction is L9 ′, and the lengths of the light sources exposed by the projection optical systems m and pL5 outside the two ends are L10 and L11, respectively. Here, the length of the pixel pattern of light = X-axis direction is the same as the pixel pattern 50 of the photosensitive substrate ρ.

10803pi f. Ptd Page 26 200304167 V. Description of the invention (22) In the exposure process of this embodiment, as shown in FIG. 8, the entire exposure pattern on the photosensitive substrate p is divided into a length Li2 in the Y-axis direction, A division pattern 53 including a portion of the peripheral circuit pattern 51a and the pixel pattern 50, a division pattern 54 having a portion of the pixel pattern 50 in the length L13 in the Y-axis direction, and a length L14 in the Y axis direction, including the peripheral circuit pattern 51b and Three areas, such as the division pattern 55 of a part of the pixel pattern 50, are scanned for a total of three times. The length L 1 2 is the distance in the γ-axis direction between the + γ direction endpoint of the short side of the projection area 3 4 a and the -γ direction endpoint of the long side of the projection area 34d. The length L1 3 is the distance in the γ-axis direction between the + Y direction endpoint of the long side of the projection area 34b and the -Y direction endpoint of the long side of the projection area 34c. The length L 丨 4 is the distance in the γ-axis direction between the + Y-direction endpoint of the long side of the projection area 34b and the -Y-direction endpoint of the short side of the projection area 34e. Further, the division pattern 53 and the division pattern 54 are overlapped at the joint portion 58a, and the division pattern 54 and the division pattern 55 are overlapped at the junction portion 58b. The joint portions 5 8a and 5 8b each overlap the joint portions 36a to 36d of the projection area 34a to 34e at the same distance. FIG. 9 is a flowchart showing the exposure method of the present invention. Hereinafter, a first embodiment of the exposure method of the present invention will be described with reference to FIG. 9. The exposure device EX starts an exposure operation (stage SA0). First, the detector 41 provided on the substrate table P S T detects the illuminance (stage SAI) of the projection leads 34a to 36e. Specifically, the control device C 0 N T outputs an instruction to the filter driving section 2 1 D to shift the light beam from the light source 6 through the filter 21 with the maximum transmittance.

10803pif. Ptd page 27 200304167 V. Description of the invention (23) Dynamic calender 21 When the calender 21 is moved ', the light beam is irradiated from the light source 6 through the elliptical mirror 6a. The irradiated light beam is transmitted through the transitional light beam 21, the translucent mirror 19, the mask M, and the projection optical system PU to PL5. Arrived on the substrate table PST. At this time, the reticle M is not supported on the reticle table MST Λ or it is evacuated to a position where no pattern or the like is formed in the lighting field. At the same time, the photosensitive substrate P is not supported on the pedestal table PST. At the same time, the detector 41 moves in the X-axis direction and the γ-axis direction, and scans the projection areas 3 4 a to 3 4 e corresponding to each of the projection optical systems PL1 to PL5. The scanned detector 41 sequentially detects the illuminance in each projection area 3 4 & ~ 346 and the illuminance% & ~ ^ in the boundary portion 353 ~ 3511. The detector 41 outputs the detection results of the illuminance including the boundary portions 35a to 35h and the projection areas 34a to 34e to the control device CONT. At the same time, a part of the light beam irradiated from the light source 6 is incident on the detector 20 by a semi-transparent mirror. The detector 20 detects the illuminance of the incident light beam and outputs the detection result of the illuminance to the control device CONT. The control device C 0 N T memorizes the illuminance of each optical path measured by the detectors 20 and 41 and the illuminances W a to W h at the border portion 35 a to 35 hours. The control device CONT is based on the detection result of the detector 41, in order to make the illuminance of each projection area 34a to 34e approximately equal, and to make (| Wa-Wb |, I .W e-W d |, 丨 W e-W f 丨) becomes the smallest. The detector 4 1 measures the illuminance while driving each of the lighting system components 10a to 10e. Therefore, the light amount of each light beam in each light path is corrected. Moreover, at this time, a part of the light beam irradiated from the light source 6 is incident on the detector 2 0 by the translucent mirror 19, and the detector 2 0 detects the incident light

200304167 V. Description of the invention (24) Beam Illumination ’The detected illuminance signal is output to the control bag and placed at Cont. Therefore, the 'control device C 0 N T is based on the illuminance of the light beam detected by the detection β 2 0. In order to make this illuminance a predetermined value, the filter driving section 2 1 D may be controlled to adjust each light amount of each optical path. The control device C 0 ΝT sets the mask M according to the target exposure amount of the illuminance detection result in the projection area 3 4a to 34e detected by the detector 41 and the exposure amount to be exposed on the photosensitive substrate P. Movement speed in synchronization with the photosensitive substrate P (stage SA2). That is, the exposure amount on the photosensitive substrate P is a relationship between the product of the illuminance and time, and the synchronized moving speed is set in a uniform manner in accordance with the target exposure amount set in advance in accordance with the illuminance on the photosensitive substrate P detected by the detector 41. For example, when the illuminance is low, the synchronous moving speed is set to a low speed ', and when the illuminance is high, the synchronous moving speed is set to a high speed. Here, the control device CONT memorizes the relationship between the synchronous movement speed and the illuminance (data table) to obtain a predetermined light quantity. The control unit CONT sets the synchronous moving speed based on the above relationship. The control unit CO NT memorizes information on the set synchronized movement speed. Next, the photomask M and the photosensitive substrate P are transported and supported on each photomask table MST and the substrate table PST. The control unit CONT uses a positioning system (position detection section) 4 9 a and 4 9 b to position (position) the photomask M and the photosensitive substrate P (stage SA3). Specifically, when the reticle M and the photosensitive substrate P are transported and supported on each reticle table M S T and the substrate table P S T, they are constituted by a wavelength that is not photosensitive to the photoresist.

10803pif. Ptd Page 29 200304167 V. Description of the invention (25) The illumination light formed from the positioning system 4 9 a is incident on the -Z axis through a mirror (not shown). The emitted illumination light is irradiated on the mask positioning mark 5 6a of the mask μ, and at the same time, the substrate positioning mark 5 7 a is irradiated on the photosensitive substrate through the mask M through the projection optical system 7L1 located at the outer position. The light (reflected light) generated by positioning the substrate on the substrate 5 7 a is incident on the positioning system 4 9 a via the projection optical system p l 1, the mask%, and the reflector. On the one hand, the reflected light reflected on the mask positioning mark 5 6a is also incident on the positioning system 4 9 through the dioptric mirror. The positioning system 4 9 a detects each positioning mark based on the reflected light from the mask M and the photosensitive substrate p. Weaving 56a, 57a. Specifically, a positioning optical system 4 9 a via an unillustrated image-forming optical system in the positioning system 4 9 a enables the reflected light from the photomask M and the photosensitive substrate p to be simultaneously imaged in a two-dimensional [CD On the imaging surface, a daylight image of the superimposed mask positioning mark 5 6a on the transmission portion 48 of the substrate positioning mark 5 7a is subjected to image processing. The detection result of the positioning system 4 9 a is output to the control device CO NT. The control device CO NT is based on the detection result of the positioning system 4 9a to find the positions of the mask positioning mark 5 6a and the substrate positioning mark 5 7a. The amount of deviation, that is, the amount of deviation between the position of the photomask M and the photosensitive substrate P. Next, the substrate table PST moves the mask table MST in the + Z axis direction. However, in the same procedure as above, the positioning system 4 9 b detects the mask positioning mark 5 6 b and the substrate setting mark 5 7 b. The detection result of the positioning system 4 9 b is output to the control device (: 〇) ^, and the control device 〇01 ^ 11 is based on the detection result of the positioning system 496 to determine the amount of position deviation between the photomask M and the photosensitive substrate P. From the result obtained above, the control device CO NT moves the photomask table MST or the substrate table PST slightly to align the position of the photomask M and the photosensitive substrate P.

10803pif.ptd Page 30 200304167 V. Description of the invention (26) Moreover, at this time, the illumination light is irradiated on the mask positioning mark 5 6b of the mask M, and at the same time, the projection optical system PL is transmitted through the mask M through the outer position. 5 The substrate positioning mark 57b irradiated on the photosensitive substrate P. Furthermore, in the same order as the detection sequence of the mask positioning marks 56a, 56b and the substrate positioning marks 5 7a, 5 7b, the mask machine MST and the substrate machine PST are moved in a stepwise manner while the light is moved. The cover weaving 4 6a to 4 6d and the substrate weaving 4 7 a to 4 7 d sequentially overlap, and the positioning system 4 9 a and 4 9 b detect the position of the weaving. The detection results of the positioning systems 49a and 49b are output to the control device CONT. The control device C0NT is based on the detection results of the positioning systems 49a and 49b to determine the position deviation of the mask marks 46a ~ 46d and the substrate marks 47a ~ 47d. the amount. The control device CO NT detects the amount of positional deviation between the photomask M and the photosensitive substrate P based on the result obtained above. The controller CONT is set based on the required amount of positional deviation, and sets the correction amount for the relative displacement, rotation, and magnification of the mask M and the photosensitive substrate P (stage SA4). That is, the control device CONT is used to detect the position of the mask μ and the photosensitive substrate ρ using the positioning systems 49a and 49b to detect the position information of the mask mark weaving 46a ~ 46d and the substrate}. The position information is statistically collected to determine the position of the entire pattern set on the photosensitive substrate P. According to the required position information and the ideal position (physical and similar characteristics, that is, displacement, rotation, magnification, and grid), The amount of the pattern. However, the deformation patterns of the photosensitive substrate ρ and then of the photosensitive substrate P can be superimposed in a predetermined positional relationship, and the resulting pattern can be used as the displacement adjusting mechanism 23 provided for PU to PL5. Projection optical system, avoidance adjustment mechanism 28, 31,

10803pif.ptd p. 31 200304167

Figure and Fifth, Description of the Invention (27) Each correction amount of the magnification adjustment mechanism 27 is to use X34a, y34a, R34a, sk, etc. described in Figures 5A, 5B 6A, and 6B. In other words, the device CONT is based on the positioning results of the positioning systems 49a, 49b, and the driving amounts of the driving devices 50A, 50B, 51A, 51B, 52. Secondly, the control device CONT is based on the "moving speed" set in stage SA2 to find the displacement mechanism 2 3, the rotation adjustment mechanism 2 8, 3 1 and the magnification adjustment mechanism 2 7 provided in each projection optical system PL and PL5. Correct the speed, that is, use the sun and moon Vx34a, Vx34a, Vx34a, VSk, etc. as shown in Figs. 5A and 5B and Figs. 6A and 6B (stage SA5). In other words, the control device CONT is based on the synchronized movement fan set to set the riding of the driving devices 50A, 50B, 51A, 51B, 52_,

In this way, by setting the driving speed of the driving device I according to the synchronous moving speed, although the synchronous moving speed is changed, the pattern formed on the photosensitive substrate p ^ can be overlapped with the second pattern in a predetermined positional relationship. This situation will be described with reference to Figs. 10A, 10B, and 10C. Fig. 10A is a diagram showing the relationship between the synchronous moving speed Va of the photosensitive substrate p scanned in the direction of the arrow xl and the driving speed Vd of the correction mechanism according to the deformation of the photosensitive substrate p as appropriate. In addition, as described above, the deformation of the photosensitive pad P can be obtained based on the detection results of the positioning systems 29a and 49b. In Fig. 10A, the target non-linear correction amount shown by the dashed line is consistent with the actual non-linear correction amount shown by the solid line. The positions P1 to p5 are the same as those shown in Fig. 13A, and represent positions set at regular intervals on the photosensitive substrate P in the scanning direction. In addition, the interval Ta in FIG. 10A represents a reference point (for example, a projection light).

U'l

10803pif.ptd Page 32 200304167 V. Description of the invention (28) The optical axis of the learning system passes from position P1 (P2, P3, P4) to position P2 (P3, P4, P5). That is, when the time D3 is short, it means that the synchronous moving speed is fast, and when the time is long, it means that the synchronous moving speed is slow. However, the driving start point of the correction mechanism is a point in time when the light-sensitive substrate moves in the scanning direction, that is, a point in time when each position p 1 to P 5 of the set reference point passes. As shown in FIG. 10B, for example, when the output of the light source 6 is low and the illuminance detected by the detector 4 1 is low, the synchronous moving speed Va is slowed down to Vb. At this time, the time Pb is longer than the time Pa. ) According to the synchronous moving speed, the driving speed Vd of the correction mechanism is reduced to Vdl. Although the correction mechanism and the driving start point are set at the time when each position P1 ~ P5 passes the reference point, the indicated by the dotted line can be made. The target non-linear correction amount is consistent with the actual non-linear correction amount shown by the solid line. a, aspect ', as shown in FIG. 10C, for example, the light source 6 V is changed by the method, and the detected illuminance of the external detector 41 is increased, so that the synchronous movement speed is relatively large compared to the occasion (at this time, 1 ^ It is shorter than the time Ta), move in synchronization with ^ VA0, dangling vc 'by making the driving speed of the correction mechanism faster than Vd EM DR, = make the driving start point of the correction mechanism, set at 2 t at each position It can also make the target non-linear correction of heavy spots shown by the dotted line '^ the actual non-linear correction amount shown in /, through the line. μ person m ^ ′ In the 10th, 10th, 10th, and 10th C diagrams, the correction speed and the correction amount are matched with the step instruction a i ▲ said that the π-direction movement is successively set with a continuous value. Thereby, correction of image characteristics is performed by a correction machine. ° ， ’Instead of setting the correction speed according to the synchronous moving speed,

10803pif.ptd Page 33 200304167 V. Description of the invention (29) Set the correction amount at each position in the scanning direction on the photosensitive substrate P according to the synchronous moving speed. In addition, in the description using the drawings Nos. 10A to 10C, although the driving start point of the correction mechanism is a fixed time point when the photosensitive substrate P moves in the scanning direction, that is, is set at each position P1 to P5 passing the reference point At the point of time, the time response characteristic of the driving device can also be obtained in advance, and the result of this determination and the synchronous moving speed can be used to set the driving start point of the driving correction mechanism. For example, when the synchronous moving speed becomes faster, the delay of the motor response of the drive device from time may not be able to track the synchronous moving speed. In this case, the time response characteristic of the motor is obtained in advance. For example, when the synchronous moving speed becomes higher than the set value, the control device C0NT uses the time response characteristic obtained above to set the timing of the drive start signal to the motor. The time points at which the positions P 1 to P 5 pass the reference point are earlier than the time point. Therefore, even when the synchronous moving speed is fast, the image characteristics can be corrected smoothly by the correction mechanism. As described above, when the correction speed and the correction amount of the correction mechanism are set based on the synchronous moving speed, the exposure processing can be actually performed on the photosensitive substrate P. First, exposure processing corresponding to the 53 parts of the division pattern is performed. In this case, the lighting shutter 1 2 corresponding to the lighting system component 1 0 e of the projection optical system PL5 is inserted into the optical path via the shutter driving unit 1 2 D, as shown in FIG. 8, corresponding to the projection area 3 4 e. The illuminating light of the optical path is blocked. At this time, the lighting shutters 12 of the lighting system components 10a to 10d open each optical path. Thereby, in the mask M, an illumination area (stage 1) in which the length in the Y-axis direction including a part of the peripheral circuit 45a and the pixel pattern 44 is set to L1 2 is provided.

10803pif. Ptd Page 34 200304167 V. Description of the invention (30) SA6) 〇 Secondly, the control device C0NT moves the photomask M supported by the photomask table MST and the photosensitive substrate P supported by the substrate table PST in synchronization with each other. The first scan exposure is performed in the X-axis direction (stage SA7). Thus, as shown in Fig. 8, on the photosensitive substrate P, the division pattern 53 corresponding to the projection area set by the projection optical systems PL1, PL2, PL3, and PL4 is exposed. Here, the synchronous moving speed at the time of scanning exposure is a value set in step S A 2. Scanning exposure is based on a correction mechanism (displacement adjustment mechanism 23, rotation adjustment mechanism 28, 31, and magnification adjustment mechanism 27) that sets the driving speed or amount in accordance with the synchronous moving speed. — Surface correction image characteristics (displacement, rotation, and magnification) Scan exposure is performed on one side. The driving speed or driving amount of the correction mechanism at this time is set in stage SA4 or stage SA5. Next, in order to perform the second scanning exposure, the controller CONT causes the substrate table PST to align the predetermined position. The specific system control device CONT enables the substrate machine PS to move at a fixed distance PS1 step in the + Y direction at the same time to perform fine adjustment of the position. This distance PS1 corresponds to three points of the distance L 3 in the Y-axis direction of the projection area. In addition, the control unit CONT causes the mask table MST to align the predetermined position. Specifically, in order to make the pixel pattern 50 continuous, the control device CONT moves the mask unit MST to the Y-axis direction by a predetermined distance to the pattern bonding portion 58a on the photosensitive substrate ρ (stage SA8). The control device CONT uses the relationship between the second scanning exposure of the projection areas 34b and 34c to correct the illuminance of the projection areas 34b and 34c.

10803pif.ptd Page 35 200304167 V. Description of the invention (31) Furthermore, the 'control device CONT' corrects the illumination in the projection area 34d and the projection area 34b. Among them, the projection area 34d is to expose the bonding portion 5 8a of the photosensitive substrate P during the first scanning exposure, and the projection area 34b is to expose the bonding portion 5 8a during the second exposure. Specifically, in order to make the projection areas 3 4 b, 3 4 c ends 3 5 c, 3 5 d illuminance difference (丨 W c-W a 丨) ′ and the projection area 3 during the first scanning exposure 3 The difference in illumination f (丨 Wg-Wb 丨) between the end 3 4 g of 4 d and the projection area 3 4 b at the time of the second scanning exposure is minimized. For each of the lighting system components 1 Ob and 1 Oc, the detector 20 is used to drive the filter 21 while measuring the illuminance of each optical path. Thereby, the light quantity of the light beam of each optical path is corrected. The control device CONT is a lighting system module 10a, 10d, and 10e corresponding to the projection optical systems pLi, pL4, and pL5. The lighting shutters 12 are inserted into the optical path via the shutter driving unit 12D, and The illumination light of the light paths of the projection areas 34a, 34d, and 34e is shielded (the light system components 丨 0b and 10c = the bright shutter 1 2 series make each light path open). As a result, the illuminating area in which the length of the part including the pixel pattern 4 4 in the γ-axis direction is set to L3 in the mask µ (step SA9). The control unit CONT causes the photomask µ and the photosensitive substrate p to move synchronously in the X-axis direction again for a second scanning exposure (stage SA10). φThis', as shown in FIG. 8, on the photosensitive substrate p, the division pattern 5 4 of the domain is illuminated corresponding to the illumination set by the projection areas 34 b and 34 c of the projection optical systems PL 2 and PL 3. 8a and the division pattern 5 3 are exposed in a repeated state. Here, the synchronous moving speed during scanning exposure is set in stage SA 2

200304167 V. Description of Invention (32) In addition, the scanning exposure is based on a correction mechanism (displacement adjustment mechanism 23, rotation adjustment mechanism 28, 31, magnification adjustment mechanism 27) that sets the driving speed or amount in accordance with the synchronous moving speed—surface correction image characteristics (displacement, rotation, magnification) Scan exposure is performed on one side. The driving speed or driving amount of the correction mechanism at this time is set in stage SA4 or stage SA5. Next, the control device CONT moves the substrate table PST in the + Y direction in steps of PS2. This distance PS2 corresponds to two points of the distance L3 in the Y-axis direction of the projection area. In addition, the control device CO NT causes the mask pattern MST to position the mask M at the first scanning exposure on the pattern bonding portion 58b on the photosensitive substrate P at a predetermined distance to make the pixel pattern 50 continuous. Displacement in the direction of the Z axis (stage SA1 1). The control device CONT performs the relationship of the third scanning exposure in the projection areas 34b to 34e, and corrects the illuminance in the projection areas 34b to 34e. Furthermore, the control device CO NT corrects the illuminance in the projection area 34c and the projection area 34b. Among them, the projection area 3 4 c is to expose the bonding portion 5 8b of the photosensitive substrate P during the second scanning exposure, and the projection area 3 4b is to expose the bonding portion 5 8 b during the third scanning exposure. The specific system is to make the illuminance difference between the end portions 35c and 35d, between the end portions 35e and 35f, and between the end portions 35g and 35b of the projection area 34b to 34e (丨 Wc-Wd |, 丨 We-Wf |, | Wg-Wh |) and the illuminance difference between the end 35e of the projection area 34C at the second scanning exposure and the end 3 3 b of the projection area 3 4 b at the third scanning exposure (I Wc-Wb |) As a minimum, the control device cONT drives the filter 21 while measuring the illuminance of the light beams of each optical path with the detector 20 for each of the lighting system components 10b to 10e. Thereby, the light quantity of the light beam of each optical path is corrected.

10803pi f. Ptd page 37 200304167 V. Description of the invention (33) The control device CONT corresponds to the projection optical system. PL1's lighting system component 1 0 a's lighting shutter 12 is inserted into the optical path via the shutter driving section 16 and as shown in FIG. 8, the lighting system of the optical path 3 4 a in the projection area is shielded (lighting system The illumination shutters 12 and 2 of the components 10b to 10e open each light path). As a result, a lighting area having a length L 1 4 in the γ-axis direction including a part of the peripheral circuit pattern 45b and the pixel pattern 44 is set in the mask M (step SA1 2). The control device CONT causes the photomask M and the photosensitive substrate P to move synchronously in the X-axis direction for a third scanning exposure (step S A 1 3). Therefore, as shown in FIG. 8, on the photosensitive substrate p, the division patterns 55 corresponding to the illumination areas set by the projection areas 3 4 b to 3 4 e of the projection optical systems PL 2 to PL 5 are bonded together. The portion 58b and the division pattern 54 are exposed in a repeated state. Here, the synchronous moving speed at the time of scanning exposure is a value set in stage SA2. In addition, the scanning exposure is performed by a correction mechanism (displacement adjustment mechanism 2 3, rotation adjustment mechanism 2 8, 3, 1 magnification adjustment mechanism 2 7) that sets a driving speed or a driving amount according to the synchronous moving speed. One side corrects image characteristics (displacement, rotation, Magnification). The driving speed or driving amount of the correction mechanism at this time is set in stage SA4 or stage SA5.如此 In this way, using a mask M of one piece, the exposure of the bonding of the light fist P which is larger than the mask M can be completed (stage SA1 4). As described above, the relationship between the correction speed or the amount required to correct the image characteristics of the pattern projected on the photosensitive substrate p is set according to the synchronous moving speed of the mask M and the photosensitive substrate p. Although the synchronous moving speed may be changed,

〇803pif. Ptd Page 38 200304167 V. Description of the invention (34) Make the target correction amount consistent with the actual correction amount. Therefore, the patterns can be superimposed at a predetermined positional relationship with good accuracy, and exposure processing with excellent accuracy can be performed. Here, the exposure method in this embodiment is a scanning exposure relationship in which the photomask M and the photosensitive substrate P are moved synchronously while exposing, and only the displacement adjustment mechanism is set as a correction mechanism, and the displacement adjustment mechanism is used to correct Scanning exposure is performed on the side of the image for non-linear correction. On the other hand, each of the displacement adjustment mechanism, rotation adjustment mechanism, and magnification adjustment mechanism is provided as a correction mechanism. By performing scanning and exposure while correcting the position or size (shape) of the image with these three adjustment mechanisms, it is possible to perform more accurate precision. Non-linear correction. In addition, the exposure apparatus EX of the above embodiment is a so-called multi-lens scanning type exposure apparatus having a plurality of adjacent optical systems adjacent to each other. The present invention can also be applied to a scanning type exposure apparatus having a single projection optical system. Moreover, in the above-mentioned embodiment, although the synchronous moving speed of one scanning exposure is described at a constant speed, a continuous change may be used. The correction mechanism can perform non-linear correction of the image by setting one of the correction speed and the correction amount to a continuous value in accordance with the change of the synchronous moving speed. Next, a second embodiment of the exposure method of the present invention will be described with reference to FIG. 11. The exposure device EX starts an exposure operation (stage SB0). The reticle M and the photoreceptor are made on the respective reticle table MST and the substrate table PST.

10803pif. Ptd Page 39 200304167 V. Description of the invention (35) After the board P is transported and supported, the control device C0NT uses a positioning system (position detection section) 4 9 a, 4 9 b to detect the mask mark fiber 4 6 a ~ 4 6 d and substrate weaving 47a to 47d. Based on this detection result, the pattern displacement, rotation, magnification, and further the deformation amount of the photosensitive substrate P are determined (stage SB1). Next, the control device CO NT is set according to the positioning results of the positioning systems 49a and 49b, that is, the position of the photomask M or the photosensitive substrate P, to set the driving speed or driving amount of the driving device that drives the correction mechanism (stage SB2). However, the control device CONT corrects the image characteristics based on the correction speed or amount set according to the position of the mask M or the position of the photosensitive substrate P, and simultaneously projects the pattern of the mask M and the photosensitive substrate P to project the pattern of the mask M Exposure to the photosensitive substrate P. At this time, the moving speed (scanning speed) of the mask table MST and the substrate table PST in the synchronous moving direction is detected by the speed detection devices 7 1 and 7 2. The detection results of the speed detection devices 7 1 and 7 2 are output to the control device CONT °, and the illuminance corresponding to each light path of each projection area 3 4 a to 3 4 e is set in each lighting system during scanning exposure. The detectors 20 of the components 10a to 10e are detected. The detection result of the detector 20 is output to the control device CQNT (P is all SB3). Here, when the output of the light source 6 is lowered for any reason and the illuminance detected by the detector 20 is low. The low illuminance information is input via the detector 2 0. The control device CO NT is based on the negative illuminance detected by the detector 2 0. In order to make the photosensitive substrate P be exposed at a predetermined exposure amount,

10803pif. Ptd Page 40 200304167 V. Description of the invention (36) In order to reduce the scanning speed of the substrate machine PST and the mask machine MST, a new scanning speed is set (stage SB4). Also, the scanning speed of the newly set substrate machine PST and photomask machine MST is set based on the relationship between the target exposure amount and the illuminance and scanning speed (data table) stored in the control device CONT beforehand. ^ The speed information of the substrate machine PST and the mask machine MST that reduce the speed in the synchronous movement direction are detected by the speed detection devices 7 1 and 7 2. The detection results of the speed detection devices 7 1 and 7 2 are output to the control device c 0NT. The control device C0NT adjusts the correction speed and amount of the correction mechanism according to the speed change of the substrate table PST and the mask table MST. (Stage SB5). That is, when the detection results of the "speed detection devices 7 1 and 7 2 decrease from Va to Vb", the control device CONT changes the driving speed of the correction mechanism from Vd to Vdl. At this time, when the control device cONT changes the driving speed of the correction mechanism from Vd to Vdl, it does not change in steps, but cooperates with synchronous movement to change successively continuously. On the one hand, when the detection results of the speed detection devices 71 and 72 are raised from Va to Vc ', the control device CONT changes the driving speed of the correction mechanism from Vd to Vd2. At this time, when the control device cONT changes the driving speed of the correction mechanism from Vd to Vd2, it does not change in steps, but changes in sequence with the synchronous movement. In this way, the photomask M is used to complete the joint exposure of the photosensitive substrate P (stage BS6). As described above, the actual synchronous moving speed can also be detected by the speed detection devices 71 and 72 (see FIG. 1), and the control device C0NT is based on speed

10803pif. Ptd Page 41 200304167 V. Description of the invention (37) The detection results of the degree detection devices 71 and 72 are used to control the driving speed of the correction mechanism. In addition, although the correction mechanism in each of the above embodiments is a parallel plane glass plate or a right-angle prism, it is not limited to this. For example, for a displacement adjustment mechanism, a pair of deflection prisms are set on the light path of the exposure light, and by rotating this around the Z axis or moving in the Z axis direction, the position of the image on the photosensitive substrate P can also be adjusted. Moreover, the use of the exposure device EX is not limited to an exposure device for a liquid crystal that exposes a liquid crystal display element pattern on a corner glass plate. For example, an exposure device suitable for semiconductor manufacturing or a thin film magnetic head is widely used Device. The light source of the exposure device EX of this embodiment uses not only g-line (436nm), h-line (405nm), i-line (365nm), but also ArF excimer laser (193nm), F2 laser ( 157nm). The magnification of the projection optical system PL is not only a series of equal magnifications, but also any one of a reduction queue and an enlarged queue. The projection optical system PL uses far-ultraviolet light such as excimer laser, and the field glass material is quartz or fluorite, which can transmit far-ultraviolet light. The F2 laser is used as the optical system of the refracting or refracting system. / '• In the case of substrate machine PST or photomask machine MST using linear motor (丨 inear motor), it can be used, using air bearing air bearing type and using Lorentz force (L〇 rentz force) or reactance (reactionance force) of any magnetic levitation type. Also, the machine system is available

10803pif.ptd p. 42 200304167

V. Description of the invention (38) The type of moving along the guide can also be used without guide. When a plane motor is used as the driving device of the machine, either one of the magnet assembly and the armature assembly is connected to the machine, and the other of the magnet assembly and the armature ^ and ^ can be installed on the moving surface side (chassis) of the machine. The reaction force generated by the movement of the substrate table PST is as described in Japanese Patent Application Laid-Open No. 8-1 647 647 5, and the frame member can also be used to guide the ground mechanically. The present invention is also applicable to an exposure apparatus having this structure. The reaction force generated by the movement of the mask machine MST is described in Japanese Patent No. 8 ^ 330 224, and a frame member can also be used to mechanically apply the ground. * Invention Department 'can also have this structure: Open the application system, set up the optical system into the electricity, set up the wiring, and complete the project to ensure the manufacturing. The system's precision manufacturing process successively exposes the composition as described below. The patent holders need to complete the package required to complete the machine. The gas device is built. If you want to apply for a machine, please apply for a standard machine to ensure that the optical accuracy is adjusted. The set up process. The perimeter of each bank's joint project requires various academic skills. The degree of implementation of the seed adjustment process from the preparation of the sub-system, the accuracy of the adjustment of various systems before the control, the system, for example, the structure of the fine, the integration of the needs, the interconnection of the sub-system is not required The structure guarantees the exposure factor, adjusts its composition, and adjusts to various systems and mechanisms. Before and after the exposure from the speech system to the composition of each study, each electrical system is exposed to various types of devices with exposure to increase the seed package, the seed machine is integrated into the optical system, and the electronic system's sub-devices are included. The system is organized by the organization system of the various roads

200304167 V. Various precisions of invention description (39). Moreover, it is preferable to manufacture the exposure device in a clean room in which temperature and cleanliness are controlled. The semiconductor device is shown in Fig. 12 as a part of the device function and performance design stage 2 0. According to this design stage, the manufacture of the photomask (grating) stage 2 0 2 is used to manufacture the substrate (crystal) of the element substrate. Circle, glass plate) stage 2 0, the pattern of the grating is exposed to the wafer processing stage 2 04 by the exposure device of the above embodiment, and the assembly stage of the element (including the dicing process, bonding) ) Manufacturing process; packaging (packaging manufacturing process) 205, inspection stage 206, etc. to manufacture. Although the present invention has been disclosed as above with a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some modifications and retouching without departing from the spirit and scope of the present invention. The scope of protection issued shall be determined by the scope of the attached patent application.

10803pif.ptd Page 44 200304167 Brief Description of Drawings Fig. 1 is a schematic configuration diagram showing an embodiment of an exposure apparatus of the present invention. Fig. 2 is a schematic perspective view showing an embodiment of an exposure apparatus according to the present invention. Fig. 3 is a configuration diagram of a projection optical system having a correction mechanism. Fig. 4 is a plan view showing a projection area. Fig. 5A is a schematic diagram showing a displacement adjustment mechanism, and Fig. 5B is an explanatory diagram of a pattern image adjusted by displacement. FIG. 6A is an explanatory diagram of a pattern image adjusted by rotation. FIG. 6B is an explanatory diagram of the magnified pattern image. Fig. 7 is a plan view showing a pattern of a photomask. FIG. 8 is a plan view showing a pattern of a photosensitive substrate. Fig. 9 is a flowchart showing a first example of the exposure method of the present invention. Figures 10A, 10B, and 10C are schematic diagrams illustrating the case where the pattern image is exposed while adjusting the correction speed and amount. Fig. 11 is a flowchart showing a second embodiment of the exposure method of the present invention. FIG. 12 is a flowchart showing an example of a manufacturing process of a semiconductor device. Figures 13A, 13B, and 13C are schematic diagrams illustrating the subject of the conventional exposure method. Explanation of drawing symbols 2 3 Displacement adjustment mechanism (correction mechanism) 2 7 Magnification adjustment mechanism (correction mechanism)

10803pif. Ptd Page 45 200304167 Brief description of drawings 2 8, 3 1 Rotary adjustment mechanism (right-angle 稜鏡, compensation mechanism) 4 9 a, 4 9 b Positioning system (position detection section) 50A, 50B Drive device 51A, 51B drive Device 5 2 Drive device CNT Control device EX Exposure device M Photomask P Photosensitive substrate (substrate) PL1 ~ PL5 Projection optical system

10803pif.ptd Page 46

Claims (1)

200304167 VI. Application Patent Scope 1. An exposure method is an exposure method in which a mask and a substrate are moved synchronously on one side, and a pattern of the mask is exposed on the substrate through a projection optical system, which is characterized by: A correction mechanism provided on the projection optical system is used to correct an image position of the pattern projected on the substrate, and at the same time, a correction speed or a correction amount is set to correct the image position according to the synchronous moving speed. 2 · The exposure method described in item 1 of the scope of patent application, characterized in that the mask is aligned with the substrate in a position, and the correction speed or the correction amount is set according to the position alignment result. 3. The exposure method as described in item 1 or 2 of the scope of patent application, characterized in that the synchronous moving speed is set in advance according to a target exposure amount of an exposure amount exposed on the substrate, and the correction is controlled at the same time Speed or the amount of correction. 4. The exposure method according to item 1 or item 2 of the scope of patent application, characterized in that the movement speed of one of the photomask or the substrate is detected, and the correction speed or the movement speed is set according to the detected movement speed. The amount of correction. 5. The exposure method as described in item 3 of the scope of patent application, characterized in that the movement speed of one of the photomask or the substrate is detected, and the correction speed or the correction amount is set according to the detected movement speed. 6. For the exposure method of the first or second scope of the patent application, it is characterized in that the correction speed or the correction amount is set to a continuous value in conjunction with the synchronous movement. 7. The exposure method described in item 3 of the scope of patent application, characterized in that the correction speed or the correction amount is set in conjunction with the synchronous movement 10803pif.ptd Page 47 200304167 VI. The scope of patent application shall be a continuous value. 8 · The exposure method as described in item 4 of the scope of patent application, characterized in that the correction speed or the correction amount is set to a continuous value in conjunction with the synchronous movement. 9. An exposure device, which is an exposure device that makes a photomask and a substrate move synchronously, and projects a pattern of the photomask on the substrate via a projection optical system, characterized in that it includes: a correction mechanism Is provided in the projection optical system to correct an image characteristic of the pattern projected on the substrate; a driving device is used to drive the correction mechanism; and a control device is used in the driving device according to the synchronous moving speed The driving speed or the driving amount, or the driving speed and the driving amount are set. 10. The exposure device according to item 9 of the scope of patent application, comprising: a position detection unit for aligning the photomask with the base; and a control device based on the position One of the detection sections detects the result, and sets the driving speed or the driving amount, or the driving speed and the driving amount. 11. An exposure device, which is an exposure device that makes a photomask and a substrate move in synchronization while passing a pattern of the photomask onto the substrate via a projection optical system, characterized in that it includes: a correction mechanism , Set on the projection optical system, so that the projection on the 10803pif.ptd p. 48 200304167 10803pif.ptd Page 49